CORE D ? IN VITRO MODELS AND CELL CULTURE CORE PROJECT SUMMARY The In Vitro Models and Cell Culture Core continues to function as a resource for all projects in the PPG. It has provided relevant cell cultures to each of the projects and has provided cells, tissues, resources, and expertise to collaborators around the world. Listed below are some of the contributions of the Core to the PPG. The progress report publication list is at the end of this application. 1. Generation of in vitro models of pig, human, and mouse epithelia. a. In vitro models of pig airway epithelia from distinct regions of the lung. b. In vitro models of human and mouse airway epithelia for comparative studies. 2. Development of new methods and models for the study of pig and human epithelia. a. Develop methods to isolate and expand pig and human airway epithelia. b. Develop methods to isolate and culture primary pig and human airway epithelia. c. Develop methods to isolate and culture primary pig airway epithelia from small airways. d. Develop methods to maintain explants of tracheal epithelia and lung slices ex vivo. e. Develop methods to culture pig gallbladder organoids. 3. Characterization of in vitro models and native epithelia. a. Bioelectric analyses. b. Morphologic evaluation. c. Gene expression profiles, mRNA and microRNA. d. Airway surface liquid (ASL) pH determination. 4. Amplification and storage of pig fibroblasts. 5. Teach investigators at the University of Iowa and other institutions how to successfully implement the methods for our in vitro model systems. 6. Record keeping relevant to tissue acquisition, cell cultures, and phenotypes. 7. Obtain all required approvals and maintain accurate records for cell and animal studies for regulatory committees. 8. Provision of cells and tissues to investigators at other institutions. 9. Production of cultured cells for investigators in the PPG. This Core offers the resources of a highly motivated and technically sophisticated staff to the benefit of the PPG investigators. As a result, it allows investigators of the individual projects to focus their unique expertise on questions of high relevance to CF.